Advertisements
Advertisements
प्रश्न
Find the angles marked with a question mark shown in Fig. 17.27
Advertisements
उत्तर
\[\text{ In } \bigtriangleup CEB: \]
\[\angle ECB + \angle CBE + \angle BEC = 180° (\text{ angle sum property of a triangle })\]
\[40° + 90° + \angle EBC = 180° \]
\[ \therefore \angle EBC = 50° \]
\[\text{ Also }, \angle EBC = \angle ADC = 50° \left( \text{ opposite angle of a parallelogram } \right)\]
\[\text{ In } \bigtriangleup FDC: \]
\[\angle FDC + \angle DCF + \angle CFD = 180° \]
\[50° + 90° + \angle DCF = 180° \]
\[ \therefore \angle DCF = 40° \]
\[\text{ Now }, \angle BCE + \angle ECF + \angle FCD + \angle FDC = 180° (\text{ in a parallelogram, the sum of alternate angles is } 180° )\]
\[50° + 40° + \angle ECF + 40° = 180° \]
\[\angle ECF = 180° - 50° + 40° - 40° = 50° \]
संबंधित प्रश्न
The measure of one angle of a parallelogram is 70°. What are the measures of the remaining angles?
The sum of two opposite angles of a parallelogram is 130°. Find all the angles of the parallelogram.
In a parallelogram ABCD, AB = 10 cm, AD = 6 cm. The bisector of ∠A meets DC in E, AEand BC produced meet at F. Find te length CF.
Which of the following statement is true for a rhombus?
It has all its sides of equal lengths.
Which of the following statement is true for a rhombus?
It is a square.
State with reason whether the following statement is ‘true’ or ‘false’.
Every parallelogram is a rhombus.
If all pairs of adjacent sides of a quadrilateral are congruent then it is called ______.
Draw a rhombus KLMN such that its side is 4 cm and m∠K = 75°.
All rhombuses are squares.
Construct a rhombus CLUE in which CL = 7.5 cm and LE = 6 cm.
